Disazo dyestuffs and their manufacture



- Y represents hydrogen or an alk xyf r' r soda lye and thereupon 'vvith 0 kg. ofptoluene better light fast-ness in' comparison with known by diazotising and combining with a phenol capa- P n N .\1 1 I I c This invention re1ates,;toltheimanuiacture-iofj Example 1 I Valuable disazo dyestufiswhichdye animal fibres redto bluish-violet shades of-very goodfastness 7 35 t -931 dyestufi ?n ne to light. I I I I I .diamine b -sulphonic acid-azo 2zfl-aminoenaph- The new disazo dyestuffs probably correspond lf h i 1 m l 1m,- with the general f l 1 V A I knownprocessesby coupling ,diazotised e-nitraniv line-G'fsrilphoriic: acid with -2zfi-amino-naphtholw Ifi-sulphonic acid in acid solution andfreduction with sodium sulphide, or bycoupling diazotised 4- r acetyl-arnino-1-'arnino-benzene-fi sulphonic acid with 2:j8 amino-naphtho1-6 sulphonici acid in acidsolutionand saponifying) are diazotised with 7 kg. of sodium nitrite and 40kg, of hydrochloric 1' 3 0C. and-'combinedwith a' sodaalk'ai I I I I dine-solution 0195 kg. of phenol. Aftercomple- X represents vhydrogen alky}, or alkoxy tion of the coupling, which occurs ina short time, i "it"is heate d-to 75*" -"C.,'treatedwith-excessof "soda wherein roup of X and Y being 1; th t different from H, sulpho-chioride, maintained at this temperature I R, represents th residue 1 a phenol ucoupled n until the esterification has beencompleted, salted 0 t p pgsition; n I out, filtered and dried; The new dyestuffya dark I A represents an'aromatic .residue'oith'e benzene powder, dissolves violet in water, blue in conceneri I II A v I f ,trated sulphuric acidand dyes wool in the acid bath in beautiful, light-fast violet shades.

The new dyestufis exh1b1t the :advantage of Iwhen. instead of phenol thereis usedmiefsbil, I

;1,3.,6:Xyle nol for other substitution products --o f phenolcapable ofibeing coupled-inthe p-position such as'd-cresolg resorc'inol-monoalkyl ethers etc., similar; dyestuffs are formed, asalso when using other analogous mono-azo dyestuffs, such as for 3 example those produced from 2- or 3-methoxy- I I or ethoxy or 3-methyl-ei-acetylamino-l-amino-' I benzene-fi sulphonic acid and 2:8-amino-naphf I thol-G-sulpho'nic acid, instead of the above mena r tioned monoazo dyestufi'from l -acetyl-amino-l- I a'mino-benzene-6-sulphonic acid and 2:8-aminonaphthoPS-sulphonic acid. With the same result I there'may be used other aryl sulpho-chlorides of the benzene series such as for example benzene-, 03H or p-chlorobenzene sulpho-chloride.

disazo-dyestufis; especially-those of the benzidine series, containing a phenol coupled in the p-posi-i tion and being esterified with aryl sulpho-chlorides. I

According to the present invention these new dyestufis are produced, either from the mono-azo dyestuffs ble of being coupled in the p-position and subse- Example 2 quent treatment with an aryl sulpho-chloride of the benzene series; or from the diazo compoundsof the mono-azo dyestuffs I 29.3 kg; of 4-amino-4'hydroxyazo-benzene 3- sulphonic acid (obtained for example from l-oxv alyl-amino-l-aminobenzene-3-sulphonic acid by X I diazotisingand coupling with phenol and saponi l i ifying, or' froml-nitro-1-aminobenzene-3 su1- I 1 V phonic acid by diazotising, coupling with phenol I and reduction of the nitro group, or from l- SOKH chloro-1-aminobenzene-3-sulphonit3 acid by diby coupling in acid solution with 2:8-aminoazotising and coupling with phenol and exchange naphthol-G-sulphonic acid and esterifying with of the 4-position halogen atom' by the amino an aryl sulpho-chloride of the benzene series. group, by heating with ammonia underpressure) I The symbols X, Y and 1i, in these formulae have are diazotised as usual with '7 kg. of sodium nitrite V the above defined meanings. and 30 kg. of hydrochloric acid 30% and there- :45 wherein 1. The disazo dyestuffs corresponding in the free state to the formula 15 X Y wherein X represents a member of the group consisting of hydrogen, an alkyland alkoxyrgroup, Y represents a member of the group consisting of hydrogen and an alkoxy-group (one of X and Y being at the most different from by drogen)v 30 R represents the residue ot a phenol, coupled, in

the para-position and I I A'represents an aromatic residue of the benzene v series, 7 being dark powders, soluble'in water with reddish L sto bluish-violet color, dyeing animal fibres'in an acid bath violet shades of good light fastness.

,2. The disazo dyestuffs corresponding in the free state to the formula X represents a memberof the group consisting of hydrogen, an alkyland alkoxy group and free state-to the formula Y represents a member of the group consisting of hydrogen and an alkoxy-group (one of X andY being at the most different from hy- 'drogen),

being dark powders,fsoluble in water with reddish to bluish-violet color dyeing animal fibres in an acid bathxvioletishades of good light fastness. 3. The disazd' dyestuif corresponding in the free stateto the formula S0311 being a, dark powder, dissolving in water with a violet color, in concentrated sulphuric acid with a 'blue color and dyeing wool in the acid bath in beautiful, light-fast violet shades.

4; The disazo dyestufi corresponding in the SOsH being a dark powder, dissolving in water with a bluish'violet color, in concentrated sulphuric acid with a violet color and dyeing wool in the acid bath in beautiful, light-fast bluish-violet shades.

5. The disazo dyestufi corresponding in the free state to the formula OCHa v NH:

CEa-G-S OLOON=NCFN=N8 SOZH being a dark blue powder, dissolving in water with a blue color, in concentrated sulphuric acid with a dark reddish blue color and dyeing wool in the acid bath in beautiful light-fast bluish violet shades.

. ADOLF KREBSER. 

